I like to use a black permanent marker to write on the bags and containers that i freeze. Even on the non bag containers like Tupperware, Rubbermaid, butter tubs ets. to remove the ink just use a little rubbing alchol on a paper towel or cotton ball. So much for the idea"permanent marker", but it stays put until then.So far i havent had any problem with staining with this method and i dont have to worry about a label or tape coming off in the freezer. Happy day all!!